/******************************************************************************
 * Spine Runtimes License Agreement
 * Last updated January 1, 2020. Replaces all prior versions.
 *
 * Copyright (c) 2013-2020, Esoteric Software LLC
 *
 * Integration of the Spine Runtimes into software or otherwise creating
 * derivative works of the Spine Runtimes is permitted under the terms and
 * conditions of Section 2 of the Spine Editor License Agreement:
 * http://esotericsoftware.com/spine-editor-license
 *
 * Otherwise, it is permitted to integrate the Spine Runtimes into software
 * or otherwise create derivative works of the Spine Runtimes (collectively,
 * "Products"), provided that each user of the Products must obtain their own
 * Spine Editor license and redistribution of the Products in any form must
 * include this license and copyright notice.
 *
 * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES,
 * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

#ifdef SPINE_UE4
    #include "SpinePluginPrivatePCH.h"
#endif

#include <spine/VertexAttachment.h>

#include <spine/Slot.h>

#include <spine/Bone.h>
#include <spine/Skeleton.h>

using namespace spine;

RTTI_IMPL(VertexAttachment, Attachment)

VertexAttachment::VertexAttachment(const String &name) : Attachment(name), _worldVerticesLength(0), _deformAttachment(this), _id(getNextID()) {
}

VertexAttachment::~VertexAttachment() {
}

void VertexAttachment::computeWorldVertices(Slot &slot, Vector<float> &worldVertices) {
    computeWorldVertices(slot, 0, _worldVerticesLength, worldVertices, 0);
}

void VertexAttachment::computeWorldVertices(Slot &slot, float *worldVertices) {
    computeWorldVertices(slot, 0, _worldVerticesLength, worldVertices, 0);
}

void VertexAttachment::computeWorldVertices(Slot &slot, size_t start, size_t count, Vector<float> &worldVertices, size_t offset, size_t stride) {
    computeWorldVertices(slot, start, count, worldVertices.buffer(), offset, stride);
}

void VertexAttachment::computeWorldVertices(Slot &slot, size_t start, size_t count, float *worldVertices, size_t offset, size_t stride) {
    count = offset + (count >> 1) * stride;
    Skeleton &skeleton = slot._bone._skeleton;
    Vector<float> *deformArray = &slot.getDeform();
    Vector<float> *vertices = &_vertices;
    Vector<size_t> &bones = _bones;
    if (bones.size() == 0) {
        if (deformArray->size() > 0) vertices = deformArray;

        Bone &bone = slot._bone;
        float x = bone._worldX;
        float y = bone._worldY;
        float a = bone._a, b = bone._b, c = bone._c, d = bone._d;
        for (size_t vv = start, w = offset; w < count; vv += 2, w += stride) {
            float vx = (*vertices)[vv];
            float vy = (*vertices)[vv + 1];
            worldVertices[w] = vx * a + vy * b + x;
            worldVertices[w + 1] = vx * c + vy * d + y;
        }
        return;
    }

    int v = 0, skip = 0;
    for (size_t i = 0; i < start; i += 2) {
        int n = bones[v];
        v += n + 1;
        skip += n;
    }

    Vector<Bone *> &skeletonBones = skeleton.getBones();
    if (deformArray->size() == 0) {
        for (size_t w = offset, b = skip * 3; w < count; w += stride) {
            float wx = 0, wy = 0;
            int n = bones[v++];
            n += v;
            for (; v < n; v++, b += 3) {
                Bone *boneP = skeletonBones[bones[v]];
                Bone &bone = *boneP;
                float vx = (*vertices)[b];
                float vy = (*vertices)[b + 1];
                float weight = (*vertices)[b + 2];
                wx += (vx * bone._a + vy * bone._b + bone._worldX) * weight;
                wy += (vx * bone._c + vy * bone._d + bone._worldY) * weight;
            }
            worldVertices[w] = wx;
            worldVertices[w + 1] = wy;
        }
    } else {
        for (size_t w = offset, b = skip * 3, f = skip << 1; w < count; w += stride) {
            float wx = 0, wy = 0;
            int n = bones[v++];
            n += v;
            for (; v < n; v++, b += 3, f += 2) {
                Bone *boneP = skeletonBones[bones[v]];
                Bone &bone = *boneP;
                float vx = (*vertices)[b] + (*deformArray)[f];
                float vy = (*vertices)[b + 1] + (*deformArray)[f + 1];
                float weight = (*vertices)[b + 2];
                wx += (vx * bone._a + vy * bone._b + bone._worldX) * weight;
                wy += (vx * bone._c + vy * bone._d + bone._worldY) * weight;
            }
            worldVertices[w] = wx;
            worldVertices[w + 1] = wy;
        }
    }
}

int VertexAttachment::getId() {
    return _id;
}

Vector<size_t> &VertexAttachment::getBones() {
    return _bones;
}

Vector<float> &VertexAttachment::getVertices() {
    return _vertices;
}

size_t VertexAttachment::getWorldVerticesLength() {
    return _worldVerticesLength;
}

void VertexAttachment::setWorldVerticesLength(size_t inValue) {
    _worldVerticesLength = inValue;
}

VertexAttachment *VertexAttachment::getDeformAttachment() {
    return _deformAttachment;
}

void VertexAttachment::setDeformAttachment(VertexAttachment *attachment) {
    _deformAttachment = attachment;
}

int VertexAttachment::getNextID() {
    static int nextID = 0;

    return (nextID++ & 65535) << 11;
}

void VertexAttachment::copyTo(VertexAttachment *other) {
    other->_bones.clearAndAddAll(this->_bones);
    other->_vertices.clearAndAddAll(this->_vertices);
    other->_worldVerticesLength = this->_worldVerticesLength;
    other->_deformAttachment = this->_deformAttachment;
}
